The present invention relates to a gasdynamic CO.sub.2 laser and to a method for operating such a laser. In such a laser an inversion may take place simultaneously with the mixing of a cold gas with the hot combusting gas.
German Patent Publication (DE-OS) No. 2,022,876 discloses gasdynamic CO.sub.2 -lasers in which the hot gas production is accomplished by the combustion of a fuel such as gasoline or benzene and so forth with the addition of oxygen. This type of laser, however, has the disadvantage that the pressure in the combustion chamber is very high. Such pressure may be within the range of about 30 to 100 bar. As a result, it is necessary to provide powerful compressors capable of providing a high volume oxygen supply. Such compressors must have a high compression ratio which in turn makes such compressors bulky.
It has been suggested to increase the power of such gasdynamic laser systems by mixing a cold gas with the hot gas simultaneously with the occurrence of the normal inversion, produced by the adiabatic expansion in the laval nozzles.